Sensor size of the upcoming A77 might be FF.

I have noted that most people on the rumor nets believe that the A77 will be APS sensor size however I would like to question that - as I feel there is evidence that it will be full frame. Let me explain.

The Sony A55 camera is 4.9 inches side to side. The Sony A700 is 5.4 inches side to side. That can be confirmed by doing some geometry using the display size as 3 inches corner to corner diagonally and then doing the math.

So it seems that leaving out the mirror mechanics for the mirror to swing up and out of the way decreases the size of the body. In addition there is no need for space for the mirror motor. That is likely the reason that the A55 is 4.9 inches and the A700 5.4 inches. The difference side to side is one half inch or 12.5 mm.

The difference in the size of a FF frame sensor in comparison to an APS is 9 or 10 mm. So why would Sony make the camera 1/2 inch bigger when smaller is the trend and the space dictated would be less without the mirror motor and rails for the mirror to swing?

Could this be because there might be a bigger than APS sensor present. I am suspicious that this is the case.

The second point is that Sony notoriously has poor sensor noise. We know that smaller pixels increase low light noise. So if the rumors are correct about the iso will be 104,000 I would not think the tiny photosites of a 24 MP sensor in APS realestate, could gather enought light to give that sort of performance - but a full size 24MP sensor might.
Any comments?